Question: Simplify the following expression: ${-3p+9(2p+7)}$
Solution: Distribute the ${9}$ into the parentheses: $ -3p + {9(}\gray{2p+7}{)} $ $ -3p + {18p+63} $ Combine the $p$ terms: $ {-3p + 18p} + 63$ $ {15p} + 63$ The simplified expression is $15p+63$